1. Field of the Invention
The present invention relates to intravascular stents and methods of treating aneurysms, and more particularly, this invention relates to a covered stent which may be modified to seal the neck of an aneurysm located adjacent to perforating blood vessels while permitting blood to flow through the perforating blood vessels, and methods of use thereof.
2. Description of the Prior Art
Expandable stents are widely used in the treatment of vascular diseases. Typically, a stent is inserted into a stenosed blood vessel after an angioplasty to prevent the restenosis of the blood vessels. Expandable stents are also used as aneurysm covers. When a stent is placed across an aneurysm, the blood flow into the aneurysm is decreased. Decreased blood flow within an aneurysm promotes the formation of a thrombus within the aneurysm which ultimately aids in protecting the aneurysm from further expansion or rupture.
Optimally, a covered stent is positioned across an aneurysm to completely restrict the blood flow into the aneurysm. Such covered stents, typically covered with a material such as PTFE provide suitable aneurysm covers; however, these stents have certain limitations. For example, covered stents impede blood flow into or out of branching or perforating blood vessels. Thus, a covered stent may not be suitable for treating an aneurysm at or near a bifurcated blood vessel or a blood vessel having perforating vessels adjacent to the aneurysm.
Several patents and patent applications disclose covered stents with various modifications which tend to avoid these limitations inherent with typical covered stents. For example, U.S. Pat. No. 6,030,414, entitled “Variable Stent And Method For Treatment Of Arterial Disease,” discloses a covered stent having predetermined and sized lateral openings for the treatment of arterial disease at or around the intersection of multiple arteries; U.S. Pat. No. 6,497,722, entitled “Method And Apparatus For In-Vivo Tailored Stents Indicated For Use In Tortuous Anatomy,” discloses a stent having a side opening to allow unimpeded blood flow to a branching vessel at the point of stenting; and, U.S. Patent Application Publication No. 2003/0074049, entitled “Covered Stents And Systems For Deploying Covered Stents,” discloses a covered stent which may be perforated in order to allow blood flow into a side branch or bifurcated vessel.
Also, U.S. patent application Ser. No. 10/696,667, filed on Oct. 29, 2003, assigned to the same assignee as the subject patent application, discloses a covered stent for treating an aneurysm which includes a skeletal stent structure with removable slat members to permit blood to flow through a bifurcated blood vessel. Upon deployment, one or more of the slats may be removed to allow blood to flow through portions of the stent structure while others of the slats are left in place to seal the neck of an adjacent aneurysm. This patent application is made of record in the subject patent application and is hereby incorporated and made a part of the subject application.